Pi-MnO2 Functionalized Biomass-Derived Carbon as a Unique Host Matrix for Electrochemical Synthesis of 2-Phenyl Benzimidazole

Abstract

The development of efficient electrocatalysts is essential for the advancement of sustainable electro-organic synthesis. The catalytic utility of a biomass-derived carbon/PiMnO2 (inorganic phosphate manganese dioxide)-modified stainless steel electrode was demonstrated through the model electrochemical synthesis of 2-phenyl benzimidazole, selected as a representative oxidative C-N annulation reaction. The hierarchical design of the electrode improved charge-transfer behavior, which in turn enhanced electrocatalytic performance and product selectivity. The reaction was conducted in a three-electrode, single-compartment electrochemical setup at a constant oxidation potential of 1.125 V (vs SCE) under ambient conditions, enabling efficient synthesis without the need for external oxidants or harsh reagents. Detailed surface and structural analyses were conducted using Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS), while cyclic voltammetry (CV) and Electrochemical impedance spectroscopy (EIS) revealed improved electrochemical kinetics. The strategy offers a promising approach to sustainable, selective electro-organic synthesis.